Embodiments of the current invention are related to swimming and other pool maintenance and safety, using pool covers. More specifically, embodiments of the current invention relate to a pool cover automatic locking and unlocking system and method.
Among benefits of covering pools, the aspect of safety—by preventing drowning and keeping family and friends safe—is foremost. A pool cover additionally acts to prevent access by pets and uninvited visitors from entering a filled or substantially-filled pool. Additionally, a pool cover keeps dirt, leaves, and debris out of the pool when it is not in use. Another significant advantage in covering a pool is savings on operating costs, such as heating; chemicals; cleaning; water evaporation; and extended pool equipment life.
Among the manufacturers of pool covers in the world are:                Zodiac Pool Systems, Inc. 620 Commerce Way Vista, Calif. 92081, USA (and its subsidiary: Cover-Pools Incorporated, 66 East 3335 South Salt Lake City, Utah 84115)        Aquamatic Cover Systems (AMCS, Inc), Gilroy, Calif., USA        Coverstar Central, 7169 East 87th Street, Indianapolis, Ind. 46256 USA        Grando GmbH, De Gasperi-Straβe 6, D-51469 Bergisch Gladbach, Germany        DEL SAS, Z.A. La Croix Rouge, 35530 Brécé, France        
Most manufacturers produce pool covers employing flexible sheets of vinyl/Dacron material and/or cloth-like pool covers; whereas some offer semi-rigid covers constructed of interlocking profile pieces, as known in the art. Reference is currently made to FIGS. 1 and 2, which are pictorial schematic views of a pool having a prior art pool cover 5. In FIG. 1, pool cover 5 is shown deployed: partially (a); and nearly completely (b). Pool cover 5 is typically stowed (i.e. retracted) and deployed in a manual; motorized; and/or semi-automatic fashion, as known in the art. Although not emphasized in the figures, the pool is filled with water.
Pool cover 5 has a leading edge 6, as seen in the detail view of FIG. 2. Leading edge 6 typically has the shape of a rigid profile piece (i.e. “slat”) as known in the art. Pool cover 5 and leading edge 6 are typically supported after deployment in a floating configuration on/near a pool water surface 9—as shown schematically in the referenced figures. Whereas the pool cover shown in FIGS. 1 and 2 is semi-rigid and is formed of individual interlocking slats, the discussion which follows hereinbelow—specifically related to securing the pool cover once deployed—is applicable to other cover materials and configurations.
In the specification and claims, which follow hereinbelow, the terms “secure”, “lock”, “fasten”, and “attach” are used interchangeably with regard to maintaining a pool cover, once deployed and substantially covering a pool, in a configuration where the cover cannot be readily retracted (i.e. uncovering the pool). Following complete deployment (not shown in the figures) pool cover 5 is typically secured at a pool edge 8, where usually leading edge 6 is attached to the pool edge to enable the cover to fulfill a primary objective of safety, inter alia. Traditionally, straps or other fastening mechanisms (not shown in the figure) are used to manually secure leading edge 6 of deployed pool cover 5 to pool edge 8.
In many locales and countries, there are standards which define how the pool cover is secured. An exemplary standard for pool coverings and securing/locking provisions is French Standard NFP 90 308, whose disclosure is incorporated herein by reference.
An example of prior art dealing with pool covers and specifically to securing a pool cover, once deployed, is U.S. Pat. No. 5,282,282 to Shehan et al., whose disclosure is incorporated herein by reference. Shehan et al. describe an improved swimming pool construction and cover, which include a swimming pool cover laid on the water of the pool and having a marginal edge provided with one component of the two-component elongated locking member. The second component of the locking member is disposed in the pool coping or deck edge accessible at the pool interior for engagement by the locking member component on the pool cover. The locking component associated with the pool is provided in a retrofit configuration by securing a locking component to a vinyl liner bead lock secured in the vinyl liner bead channel in a pool coping. In a new vinyl-lined pool construction, a coping is provided with a secondary channel with one component of the cover locking member secured therein. In a gunnite pool, a channel is formed in the deck edge and a component of the releasable cover locking member is secured in the channel for securement of the pool cover thereto.
Champion et al., in French Patent no. FR2936829, whose disclosure is incorporated herein by reference, describe a floating cover, locking device for swimming pool basin, having an elastic tongue with free end to close inlet orifice in rest position, and operated to release passage across orifice, where device is in form of monoblock assembly. The device has a hollow shell fixed on a vertical wall of a basin of a swimming pool, where the device is in form of a monoblock assembly. The shell comprises an inlet orifice sized for permitting passage of shafts and a housing delimited by a partition having an opening and receiving the shafts. An elastic tongue has a free end for closing, in rest position, the inlet orifice, and is operated to release the passage across the inlet orifice.
Among various shortcomings of prior art cover systems and fastening/securing mechanisms and locking systems are:                Need to manually adjust and/or guide straps or other mechanisms under water and/or directly at the surface of the pool to fasten the cover;        Complicated and/or time consuming procedures to secure the fastening mechanism;        Need for relatively precise positioning of a locking mechanism located at or near the pool's edge with regard to the pool cover edge and its attachment;        Difficulty of or lack of retrofitability of pool cover fastening mechanisms to existing pools; and        High cost of the fastening mechanisms/solutions.        
As a result of the shortcomings listed, in many cases, pools covers may not be deployed completely or a cover may not be completely/correctly secured once deployed—a situation that not only defeats the advantages listed hereinabove, but which may be illegal with regard to local/governmental standards, as noted hereinabove.
There is therefore a need for a pool cover locking system that is: reliable; easy to use; preferably automatic; and which may be integrated with an existing or newly installed pool cover system in a cost-effective and a straightforward manner.